1998 Pontiac Grand Prix GTP Supercharge from North America - Comments

22nd Aug 2007, 19:31

I have an 1999 GTP and it has 137,000 miles and I have recently noticed an unusual whining noise coming from the transmission. Has anyone ever had that noise? Besides that, it runs like a champ (since I replaced the supercharger).

25th Aug 2007, 19:03

I am working on a 99 gtp and it has intermittent starting. When it doesn't start, it is due to a no spark condition. I tried an ignition module, coils packs, and a crank position sensor. Still same problem. No codes, Scanner says cam sensor received, both 3x and 18x is being read. Does anyone know what the heck is going on or ever experienced this problem? It is not heat related because it may run fine for a week and then just cranks. Please let me know. Thanks.

28th Aug 2007, 20:17

A lot of people have negative issues with the Grand Prix. I am one of them. I am bitter, but overall I LOVE my car. I have a 98 4-door GTP. Thankfully, I talked my dealer into throwing in the 7/100K warranty. My car is now 9 years old.

The only real "pissy" issue I have is that I've replaced the window regulator and motor 11 times! Yes. That is ELEVEN times. The last one was just yesterday. The first 8 were under warranty. The last 3 I paid. Cost me over $1700 for all three so far. After 70K miles, the engine blew. Had to pay out of pocket for that. At 90K the supercharger blew. Had that replaced out of pocket. At 120K I replaced just about every moving part under the hood, including all the mounts. I now have 150K on it. It has been a GREAT car. There were other stuff I replaced, but it stuff that I expect for a 9 year old car with 150K miles. Regular repairs and replacement stuff for "wear and tear".

But I tell ya... those DARN window regulator with the PLASTIC CABLE RETAINER are freaking RETARDED! DARN GM for putting it out on market like that and DARN them for not recalling them and replacing them with a METAL cable retainer. HELL, if my $80 10-speed bike can have metal cable retainers (on the brake cables)... why not my $27,000 car?!?

5th Sep 2007, 16:50

I'm an original owner of 1998 Grand Prix GTP. I do love this car. It has not been without problems, but it's done as well or better than my expectations. It now has 150,000 miles on the odo. Problems: The supercharger has been making noises at idle/no load for the last 20k miles or so. I won't bother fixing that item until it BREAKS. Windows were replaced 3 or 4 times under extended-warranty (like $1000 or so each time, ridiculous!), I'm hoping they don't break now that I'm out of warranty. I've replaced the A/C compressor and recently the condenser ($1,800 for both those jobs, total). The A/C capacity in Southern California does leave something to be desired, but I remember this always being the case. My volume knobs on the steering wheel have given up and I can't find replacement parts (that's stupid for what seems to be a part in demand). The LCD in my electro-chromatic mirror has melted away and no longer dims. She sometimes runs warm, but eventually cools down. I can smell oil, but she doesn't use any noticeable oil and I don't have any drips in the garage. The lens cover fell off my drivers side, I guess I'll order a new one. I've maintained this car well... tranny and radiator flushes, Mobil-1 5W30 since it was in diapers.

7th Sep 2007, 02:21

Do not just ignore the supercharger rumbling problem at idle and shut off; the part you more than likely need is the coupler. This part connects the nose drive shaft to the rotor shaft, and it is made of an oil soaked plastic, so it wears out. The part is only $30, and if you can drain the supercharger oil, un-tension both serpentine belts, and remove the alternator, you can do this yourself. You can take it to a dealership, but they will just tell you to replace the whole unit; the quote I received was $1970, which then went up to 2200 a few days later, go figure.

Anyway, my supercharger was doing the same thing, I refused the dealership work and purchased a rebuilt unit from PSE Superchargers, and had my mechanic put it in. When all was said and done, it cost $750 for part and labor. When the unit was off my car, I spun the pulley, there was no grinding at all, but when I wiggled it back and forth, there was space between the resistance, indicating the the coupler was bad, $140 to replace that, but I trusted the dealership's word for it.

7th Sep 2007, 16:53

A couple of people have posted about this, has anyone figured out what is going on? I have an 01 GTP with 143,000 and I have the same thing. It seems to happen when I'm under load and the rpm's are low. I've never had it happen under good acceleration.

About the TCS light going off and the Tac dropping to Zero - Engine sputters a little and then resumes just fine.

However mine will stay bogged out for a while, sometimes it will kick back in, but the tach is down for the count, other times I'm stuck on the side of the road for a min or 2 trying to get it to start. It cranks hard, but won't catch.

8th Sep 2007, 09:57

I have a 2000 GT with 138,000 miles that is doing the same thing with the tachometer dropping to zero and the "Trac Off" light coming on. As soon as the tachometer drops, the engine feels like it stops for a second an then resumes just fine. I have changed the plugs (twice), plug wires, fuel filter, and air filter. If anyone knows what the problem is, please let me know!!! Also, I agree that the plastic gears on the windows and the way they operate should be outlawed. This is an absolute joke. The senior executives at Pontiac that allowed this to go into production should have to replace all of them at their expense. I have replaced the back windows twice and now they are both not working again. Other than that I love my car. Eight years old, 138,000 miles and still get 28 mpg!!!

17th Sep 2007, 17:54

I now own a 2001 Grand Prix Special Edition 2 dr, and I've never been more pleased with any other car. It's performance has been excellent, more than expected. The only problem I have with it is the speed control, it's locks up at 105 mph. I know you're not supposed to usually ask this, but, how do I disable that? It's the only problem I've had. I race it often and until recently was undefeated. The car I was racing with lost the acceleration race, but when it came to top speed, and eventually blew past me. Any suggestions?